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Date: Sat, 5 Oct 2013 03:22:48 +1000
Subject: Re: API for custom Unicode error handlers
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:55486

On Fri, Oct 4, 2013 at 11:56 PM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> Should the module holding the error handlers automatically register them?
> In other words, if I do:
>
> import error_handlers
>
> just importing it will have the side-effect of registering the error
> handlers. Normally, I dislike imports that have side-effects of this
> sort, but I'm not sure that the alternative is better, that is, to put
> responsibility on the caller to register some, or all, of the handlers:
>
> import error_handlers
> error_handlers.register(error_handlers.namereplace_errors)
> error_handlers.register_all()

Caveat: I don't actually use codecs much, so I don't know the specifics.

I'd be quite happy with importing having a side-effect here. If you
import a module that implements a numeric type, it should immediately
register itself with the Numeric ABC, right? This is IMO equivalent to
that.

> As far as I know, there is no way to find out what error handlers are
> registered, and no way to deregister one after it has been registered.

The only risk that I see is of an accidental collision. Having a codec
registered that you don't use can't hurt (afaik). Is there any
mechanism for detecting a name collision? If not, I wouldn't worry
about it.

ChrisA